I. Field of the Invention
This invention relates generally to a self-leveling hydrometer and, more specifically, to a self-leveling hydrometer that automatically adjusts the hydrometer itself to an absolute horizontal position for accurate liquid specific gravity readout.
II. Description of the Prior Art
It is known that the proper adjustment of the specific gravity of saltwater is essential to the fish inside a saltwater fish tank. It is necessary to use a hydrometer to measure and adjust the proper specific gravity of the saltwater in a fish tank to equal that of actual seawater. Either adding salt or fresh water will conversely raise or lower the specific gravity of saltwater.
One of the prior arts listed in China patent No. 96229010.6 and No. 01229324.5, is a transparent container in a flat plastic shape fixed internally with a rotating floating plastic pointer that swings in an up and down arc. The pointer is weighted by a round disc to achieve accurate calibration. The end of the pointer points to a printed numerical specific-gravity chart etched on the outside of the plastic unit. When placed down into the fish tank, the water flows up from the bottom of the unit into an inner tube and then flows over and down into the measuring chamber. It is not necessary to put your hand in the water during the sample collection, thus avoiding the chance of contaminating the water in the tank. With the collected water sample in the chamber and the unit positioned in a perfectly horizontal position, the needle will float up to point to a number on the chart to indicate the specific gravity reading of the saltwater in the tank.
If the hydrometer is not held perfectly level, the specific gravity reading will be inaccurate. Therefore it is very difficult to hold the hydrometer level in order to take an accurate reading. Held in the hand, or set on a table that is not perfectly level, will yield inaccurate readings.
It is therefore a primary objective of the invention to provide an automatic, self-leveling hydrometer that can adjust itself to an absolute horizontal position to attain accurate specific gravity values of the saltwater.
In order to achieve the objective set forth, a self-leveling hydrometer in accordance with the present invention comprises a container with a floating measurement indicator or pointer. The container further has an upper hanging bracket that allows the container to swing freely to allow gravity to pull it to an absolute horizontal position while being held by hand or hung from a stationery hook.
An imbalanced load is in the center of the floating measurement indicator, the imbalanced load can rotate freely in the round hole on the center of the floating measurement indicator; the imbalanced load has a protrudent round plate on edge, the protrudent round plate exposes on the round hole of the floating measurement indicator.
The hidden tube has three inlets on following locations: a. on the bottom of the container, b. above the liquid level outside the measure chamber and c. on the bottom of the measure chamber.